Adjust bus schedules to assure adequate time to accomplish rail-to-bus connections, given the risk of late train arrivals at connecting stations.
Experience of the Utah Transit Authority in implementing a Connection Protection program for rail-to-bus passenger transfers in Salt Lake City.
Made Public Date


United States

Evaluation of Utah Transit Authority's Connection Protection System


The Utah Transit Authority (UTA) implemented a Connection Protection (CP) system to improve the reliability of transfers from the higher frequency light rail trains to the lower frequency bus services at selected connecting rail stations. The CP system examines the status of trains and issues a "hold at {station name} until {time}" message to buses waiting at the connecting rail stations via the bus' onboard Mobile Data Terminal (MDT), if the lateness of train is within a pre-determined time threshold. The system was completed and tested in January 2002 prior to the Winter Olympic Games in Salt Lake City. Operationally, the CP messages are triggered by the late train events. One late train could potentially trigger multiple CP messages to hold one or more buses at each of the next three down-line stations, based on the CP assignment. An evaluation was conducted to assess the performance of the CP system and the response of passengers and system operators. This lesson is based on experience with the early operation of the CP system with the objective of identifying potential improvements and offering guidance to other transit agencies elsewhere that may be considering implementing a similar system.

Lessons Learned

An important factor that influences the willingness of bus operators to wait for late trains is the tightness of their bus schedule. If a bus is late getting to a rail station and the riders miss the scheduled connection, the consequence is relatively low since there will be another train in 7 to 15 minutes depending on the time of day. However, if a train becomes late and a rider misses the bus connection it might well be two hours before that route has another bus scheduled. There would be severe consequences in this case. Bus operators who report tight schedules are less likely to wait for a late train, or to wait shorter times, than operators whose schedules are not perceived as very tight. Many transit agencies look to schedule adherence by their operators as a key performance indicator; hence, there is a built in disincentive for bus operators to create delays by waiting for late arriving passengers. The Connection Protection system is designed to help resolve these types of issues. Some lessons from UTA's experience implementing their Connection Protection system specifically related to scheduling include the following:

  • Coordinate bus schedules closely with rail schedules to maximize the likelihood of successful rail-to-bus connections. Some of the bus operators in the Utah evaluation commented that the rail and bus schedules are not adequately coordinated and adjusted to assure optimal connection time. About half of all the operators (49%) said that tight scheduling often causes them to arrive late at the rail stations. Over half of the riders on the bus (53%) reported that they have been on a bus when it arrived late at the rail station one or more times in the past month. The operators recommended making adjustments on the busiest routes first, as those are where the most problems are encountered. Realistically, however, it is a significant challenge to coordinate numerous separate schedules and competing demands system wide, and bus operator input to this process is but one of many important considerations.
  • Examine current bus schedules carefully keeping in mind the need to provide adequate time to hold buses in order to accommodate passengers transferring from late trains. Transit system managers need to examine the patterns of late train events at stations that service their bus routes and determine whether current bus schedules are adequately synchronized with the rail schedules. This will also allow a calculation of the extent to which bus schedules may need to be adjusted to accommodate the likelihood of late train events without causing serious disruptions along the remainder of the bus route. Adjustment strategies may include: extending the departure times from the stations serviced by rail, relative to the rail arrival schedules; or building in additional slack time at appropriate points on the bus route to allow operators to make up time and get back on schedule. Transit agencies are focused on planning for optimal schedule timing under normal conditions; a late train event is essentially a random event that causes unanticipated delays. The message in this lesson is to consider whether further adjustments to the "normal" schedules are appropriate in light of potential late train delays.
  • Involve potentially affected bus operators where possible in decisions regarding adjustments to bus schedules, as they are most knowledgeable about where schedules can be adjusted with the least overall system impacts and the most benefit to their customers. Some bus operators in the Utah evaluation expressed frustration that they were not consulted regarding schedule adjustments. The operators feel they are uniquely qualified based on their intimate knowledge of the conditions along their routes to advise on appropriate schedule adjustments. In addition to listening more closely to the experiences and recommendations of their bus operators, transit management also needs to solicit and be responsive to the needs and opinions of their transit customers. UTA relies upon both operator input and customer feedback, as well as hard data to support decisions regarding periodic system changes.
  • When bus trips are reported to be behind schedule by transit passengers, assess the reasons and seek solutions where problems are identified. Schedules that accommodate existing travel conditions on the bus route are the appropriate baseline against which to assess the need for additional slack to accommodate potential late rail connections. When considering potential bus schedule adjustments to accommodate late train events, it is appropriate to use schedules that reflect existing travel conditions along the bus route, net of the occasional rail transfer delays. Bus schedules that are already out of synch with day-to-day real travel conditions are not an appropriate baseline from which to build in adjustments for late rail connections.
  • Emphasize the overriding value of customer service and avoid penalizing bus operators whose schedules slip because of their efforts to wait for transferring customers. The Utah Transit Authority makes substantial efforts in the supervision and training of their bus operators to emphasize the importance of customer service over and above blind adherence to rigid schedules. Connection Protection actually offers a security blanket for operators who wait for late trains by providing a management-supported rationale for being slightly behind schedule. Transit agencies need to create an organizational culture that rewards good customer service and reinforce with their bus operators the high value attached to customer responsiveness. In regard to CP, operators need to be confident they won't be penalized for schedule delays caused by their waiting for late train connections.
  • When adjusting bus schedules, seek to balance the potential inequities that may arise when waiting for a late train connection causes on-board passengers to be delayed getting to their destination. There is a potential equity issue with a CP system that benefits some riders and creates delays for others. Bus operators in Utah reported their perception of the inequity of a CP message that requires them to wait for an uncertain number of connecting passengers (sometimes few or none) knowing that the passengers already on their bus will be delayed by the wait time. While CP offers clear benefits to rail passengers trying to make connections to buses, passengers arriving on the bus at the rail station or boarding from the station's park-and-ride depend on the bus leaving on time and adhering to its schedule along the way. When CP causes the bus to wait, that jeopardizes later bus-to-rail and bus-to-bus connections down the line for the bus riders. Waiting past the scheduled departure at the rail station is associated with missing other transfer connections and with being late arriving at their final destination, and riders who have these experiences are less likely to say they are satisfied compared with those who do not. CP may make it more likely that a bus rider will experience one or more late arrivals at their final destination, so this needs to be factored in to an overall assessment of the impact or benefit of CP and taken into account when considering schedule adjustments. Adjusting bus schedules to help accommodate these delays caused by late rail connections can help mitigate this equity problem and keep the majority of passengers on time. UTA addressed this issue as best they could in their system design business rules.
  • When a bus is behind schedule, consider assigning rail connection responsibility to the next reasonably timed bus arrival. Some of the UTA bus operators noted that CP should take into account that it may be more efficient for the system, the passengers, and the operators for a later bus scheduled to arrive in a reasonable time to make the connection instead of asking the first bus to hold. Whether this is a better option depends on the details of the schedule and where the buses are in terms of schedule adherence in a particular situation. This raises the importance of having a bus Automatic Vehicle Location (AVL) system so that the locations of their buses along their routes is known at all times. In any case, it is important to have in place negotiated business rules and the flexibility to adjust schedule holds and operating rules.

The application of a Connection Protection program in Utah has served as a useful tool that can help operators better meet the needs of their transit customers. UTA agency-wide is focused on customer service and continuous improvement of their products. The evaluation of this system identified the importance of coordinating the scheduling of bus arrivals with train arrivals, and assuring that bus operators keep the needs of their customers at the forefront, even in the face of constrained bus schedules that can make waiting for late passengers difficult to accommodate. A well-designed CP system helps achieve ITS goals to enhance efficiency, mobility, productivity and customer satisfaction.

Evaluation of Utah Transit Authority's Connection Protection System

Evaluation of Utah Transit Authority's Connection Protection System
Publication Sort Date
Jeffery Jenq, Chris Cluett, Ben Pierce and Alan Pate, Battelle
ITS Joint Program Office, U.S. Department of Transportation

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